N-ethylcarbaminomethylisoleucine

ABSTRACT

The following N-substituted amino acids have been found to combat infection with influenza virus, to counteract inflammation, or to have anti-tumor effects in mice while being relatively non-toxic in effective amounts: N- Beta -naphthylaminoethylleucine, N- Beta -naphthylaminomethylurethane, N-furfurylaminoethylphenylalanine, N-furfuryl-4-nitrophenylalanine, N-benzylvaline, N-2-fluorenesulfonylmethionine, N-2-fluorenesulfonylphenylalanine, N-lauroylleucine, N-ethylcarbaminomethylisoleucine, N- Beta -naphthylaminomethylthreonine, N-9-fluorenylacetylphenylalanine, N-myristoylisoleucine, N- Beta -naphthalenesulfonyltryptophan, and N-propionylvaline.

United States Patent Toyoshima et al.

[451 Nov. 11, 1975 N-ETHYLCARBAMINOMETHYLISOLEU- CINE Inventors: Shigeshi Toyoshima; Seizo Kanao,

both of Tokyo; Takeshi Toyoda. Sagamihara; Tadashi Suyama, Kawasaki. all of Japan Assignee: Ajinomoto Co., Inc., Tokyo. Japan Filed: Mar. 14, 1974 Appl. No.: 451,209

Related U.S. Application Data Division of Scro No. 28l.042. Aug. l6. l972. Pat. No. 3.845.097. which is a continuation-impart of Ser. No. 69.993. Sept. 4. 1970. Pat. No. 3.8Ul.633.

Foreign Application Priority Data Aug. l9. I971 Japan 46413250 Aug. l9. l97l Japan 46-63252 US. Cl 260/482 C Int. CL C07C 101/26 Field of Search 260/534 R. 482 C References Cited OTHER PUBLlCATlONS Suyama et al.. Chemical Abstracts. Vol. 66 (1967). 29058y.

Sciortino et al.. Chemical Abstracts. Vol. 70 (I969). 38057g.

Prz'nmry E.\'uminerRichard L. Raymond Armrne Agent. or FirmHans Berman [57] ABSTRACT The following N-substituted amino acids have been found to combat infection with influenza virus. to counteract inflammation. or to have anti-tumor effects in mice while being relatively non-toxic in effective amounts:

NB-naphthylaminoethylleucine. N-B-naphthylaminornethylurethane. N-furfurylaminoethylphenylalanine. N-furfuryl-4-nitrophenylalanine. N-benzylvaline. N-2-fluorenesulfonylmethionine. N-2-fluorenesulfonylphenylalnnine. Nlauro vlleucine, N-ethylcarbaminomethylisoleucinet N-B-naphthylamin0methylthreonine. N-9-fluorenylacetylphenylalanine. N-myristoylisoleucine. N-B-naphthalenesulfonyltryptophan. and N-propionylvaline.

1 Claim. No Drawings N-ETHYLCARBAMINOMETHYLISOLEUCINE This application is a division of application Ser. No. 281,042, filed Aug. 16, 1972, now U.S. Pat. No. 3,845,097, which in turn is a continuation-in-part of the copending application Ser. No. 69,993, filed on Sep. 4, 1970, now U.S. Pat. No. 3,80l,633,

As has been disclosed in our earlier application, certain N-substituted amino acids are effective in combating infection with influenze virus in vivo.

it has now been found that other N-substituted amino acids have similar antiviral effects, but also compare favorably with hydrocortisone and acetylsalicylic acid in their therapeutic index values as antiinflammatory agents, and with Mitomycin-C and Bleomycin in their therapeutic index values for anti-tumor activity in mice.

While the compounds of the invention are useful in the form of the free acids, the more soluble salts with pharmaceutically acceptable bases, particularly the alkali metal salts, the alkaline earth metal salts, and organic amine salts. such as the sodium, potassium, magnesium, calcium, ammonium, monoethanolamine and diethanolamine salts which are generally more soluble in water than the free acids, and are not more toxic than the free acids in equimolar amounts.

The compounds of the invention are administered orally or parenterally in therapeutic compositions which contain one or more of the compounds as active agents in combination with a pharmaceutical carrier which may be solid or liquid, depending on the intended mode of application. Liquid compositions may be formulated in a conventional manner for oral application or for injection in dosage unit form.

The solid compositions, such as tablets, pills, powders, or granules, are prepared by combining the active agents of the invention with solid pharmaceutical carriers conventional in themselves, such as calcium carbonate, lactose, sucrose, sorbitol, mannitol, starch, amylopectin, methylcellulose, or gelatin. Compacting of the comminuted ingredients may be facilitated by the use of magnesium stearate, calcium stearate, or polyethylene glycol.

Orally applicable liquid compositions may be emulsions, solutions, or suspensions of the active agents in water, liquid paraffin and like pharmaceutically acceptable inert liquids which may additionally contain surface active agents to keep the active agents and other ingredients dispersed in the liquid carrier, and adjuvants for improving the taste or odor of the composition, as is well known in itself.

In preparing compositions of the invention for parenteral application. it is preferred to disperse the N-substituted amino acids of the invention in sterilized water containing enough alkaline material to dissolve the active agents, and to transfer dosage units of the solution to vials which are sealed thereafter.

The compounds of the invention differ from each other in their therapeutic effects and their toxicity. In their use against influenze virus and as anti-tumor agents in mice, the desired therapeutic effects may be achieved with some by a dosage of 400 mg per day applied orally or 200 mg per day applied parenterally, whereas others may need to be administered orally at a rate of 2,000 mg per day or parenterally at 1,000 mg per day. A single daily dose is preferred. As anti-inflammatory agents, the compounds of the invention may be 2 used in humans in dosages ranging from 50 to 4000 mg per day, usually orally. Preferably, they are used at a rate of 200 2000 mg per day and in small dosage units administered not more than a couple of hours apart. More or less frequent and larger and smaller unit dosages are, of course, also possible.

Those compounds of the invention which exist either in optically active (D or L) forms or in the optically inactive racemic form are equally effective in all forms.

Only N-benzylvaline, N-lauroylleucine and N-propionylvaline were known heretofore. The other eleven N-substituted amino acids enumerated above are new, but are readily prepared by means of procedures known in themselves. The Schotten-Baumann reaction may be used in preparing the N-2-fluoroenesulfonyl derivatives of methionine and phenylalanine, the N-9- fluorenylacetyl derivative of phenylalanine, the N- myristoyl derivative of isoleucine and the N-B-naphthalenesulfonyl derivative of tryptophan. Furfural may be reacted with 4-nitrophenylalanine in an alkaline aqueous medium in the presence of sodium borohydride to N-furfuryl-4-nitrophenylalanine. B-Naphthylamine may be reacted with leucine, urethane or threonine in the presence of formaldehyde in preparing the N-Bmaphthylaminomethyl derivative of leucine, urethane or threonine. Urethane may be reacted with isoleucine in the presence of formaldehyde to yield the N- ethylcarbaminomethyl derivative of isoleucine, and furfurylamine may be reacted with phenylalanine in the presence of formaldehyde to yield the N-furfurylaminomethyl derivative of phenylalanine.

The following Examples further illustrate the preparation of the N-substituted amino acids of this invention, of their salts, and of compositions containing the active agents of the invention.

EXAMPLE I A solution of 14.3 g B-naphthylamine in 100 ml 60% aqueous ethanol was added to a mixture of 13.1 g L- leucine, 60 ml 37% formaldehyde solution and 250 ml 60% aqueous ethanol. The mixture so obtained was refluxed at C for 1 hour on a water bath. A small amount of oily material precipitated and was filtered off. The filtrate was concentrated in a vacuum to precipitate crystals of N-B-naphthylaminomethyl-L-leucine which were filtered off, washed with acetone, and recrystallized from absolute ethanol. The purified, very small crystals weighed 18.9 g (66% yield) and melted at 199C.

Elementary analysis: Calculated for C H,,O,N,: 71.30% C; 7.74% H; 9.74% N. Found: 72.08% 7.71 9.48.

EXAMPLE 2 A solution of 2.86 g B-naphthylamine in 25 ml 60% aqueous ethanol was added to a mixture of L8 g urethane, 6 ml 37% formaldehyde solution and I6 ml 60% ethanol, and then an equivalent amount of oxalic acid was added. The mixture was allowed to stand whereby crystals of N-fl-naphthylaminomethylurethane oxalate were gradually precipitated. They were filtered off and recrystallized from absolute ethanol. The purified, rhombic crystals weighed 1.76 g (30% yield) and melted at 202C.

Elementary analysis: Calculated for C H O INM: 9.68% N.

Found: 9.37.

EXAMPLE 3 A solution of 2.14 g furfurylamine in 230 ml 90% aqueous ethanol was added to a warm solution of 3.3 g L-phenylalanine in 30 ml 37% formaldehyde solution. The resultant, pale brownish, clear solution was refluxed for hours on a water bath. A small amount of insoluble material was filtered off, and the filtrate was concentrated in a vacuum. The precipitated crystals of N-furfurylaminomethyl-L-phenylalanine were filtered off and crystallized from a mixture of absolute ethanol and anhydrous ether. The purified, very small crystals weighed 2.06 g (36.5% yield) and melted at 170C.

Elementary analysis: Calculated for C,,H,;N,O;,.%A H O: 63.50% C; 6.72% H. Found: 63.33 7.23.

EXAMPLE 4 4.8 g Furfural was added to a solution of 10.5 g L-4- nitrophenylalanine in 25 ml 2N sodium hydroxide solution with stirring, and thereafter a solution of 0.6 g sodium borohydride in a little water was added in small batches with ice cooling to keep the temperature at C. After stirring for 30 minutes, 4.8 g furfural and 0.6 g sodium borohydride were further added. Stirring was continued for an additional 2 hours. The unreacted furfural was extracted with ether, and the aqueous layer was acidified with dilute hydrochloric acid to precipitate crystalline N-furfuryl-L-4-nitrophenylalanine. When washed with absolute ethanol and recrystallized from 40% acetic acid, the needle-shaped crystals weighed 18.8 g (65% yield) and melted at 240C. [a],, 23.75 (C=2.00, IN NaOH).

Elementary analysis: Calculated for C H O N,: 57.93% C; 4.86% H; 9.65% N. Found: 58.20 5.10 9.54.

EXAMPLE 5 21.2 g Benzaldehyde was added to a solution of 23.4 g L-valine in 100 ml 2N sodium hydroxide solution with stirring. To the mixed solution was added a solution of 2.28 g sodium borohydride in a small amount of water. After stirring for 1 hour, 21.2 g benzaldehyde and 2.28 g sodium borohydride were further added, and stirring was continued for an additional 2 hours. The unreacted benzaldehyde was extracted with ether, and the aqueous layer was neutralized to pH 7.0 with dilute hydrochloric acid to precipitate N-benzyl-L-valine crystals. The crystals were filtered off, washed with water and ethanol, and recrystallized from acetic acid. The purified, needle-shaped crystals weighed 33 g (80% yield) and melted at 274C. [01],, 18.50 (C=2.0, 6N HCl).

Elementary analysis: Calculated for C,,H O,N: 69.53% C; 8.27% H; 6.76% N. Found: 69.43 8.44 6.81.

EXAMPLE 6 A solution of 10.6 g 2-fluorenesulfonyl chloride in 150 ml acetone and a solution of 10.6 g sodium carbonate in 80 ml water were added dropwise alternatively over a period of 30 minutes with stirring to a solution of 5.9 g DL-methionine in ml 10% sodium hydroxide solution at room temperature. Stirring was continued for 30 minutes at 50C and for 3 additional hours at room temperature. The reaction mixture was then made acid to Congo Red with dilute hydrochloric acid, and partly evaporated in a vacuum to remove the acetone. The precipitated crystals of N-2-fluorenesulfonyl- DL-methionine were filtered off, washed with water and ethanol, and recrystallized from acetic acid. The

4 purified, needle-shaped crystals weighed 11.2 g yield) and melted at 168C.

Elementary analysis: Calculated for CmHwNsg: 57.27% C; 5.07% H; 3.71% N. Found: 57.24 5.27 3.68.

EXAMPLE 7 A solution of 5.3 g Z-fluorenesulfonyl chloride in 150 ml acetone and a solution of 5 g sodium carbonate in 50 ml water were added dropwise alternatively with stirring to a solution of 3.3 g L-phenylalanine in 10 ml 10% sodium hydroxide solution. Stirring was continued for 4 hours at 50C. and the reaction mixture was then adjusted to pH 3-4 with dilute hydrochloric acid and partly evaporated in a vacuum to remove the acetone and to induce crystallization of N-2-fluoroenesulfonyl- L-phenylalanine. The crystals were filtered off, washed with water, and recrystallized from acetone. The purified, needle-shaped crystals weighed 5.2 g (66% yield) and melted at 141C. [al 2.86 (C=2.094, acetone).

Elementary analysis: Calculated for C,,H,,O NS: 67.15% C; 4.86% H; 3.56% N. Found: 66.94 5.21 3.38.

EXAMPLE 8 21.9 g Lauroyl chloride and a solution of 15.9 g sodium carbonate in 110 ml water were added dropwise alternatively over a period of 30 minutes with stirring to a solution of 13.1 g L-leucine in 40 ml 10% sodium hydroxide solution at room temperature. After stirring for 3 hours at that temperature, the reaction mixture was made acid to Congo Red with dilute hydrochloric acid. The precipitated crystals of N-lauroyl-L-leucine were filtered out, washed with water and recrystallized from dilute methanol. The purified. plate-shaped crystals weighed 28.2 g yield) and melted at 109C. [01],," 16.24 (C=l.l08, absolute ethanol).

Elementary analysis:

Calculated for c,H,,o,N= 68.96% C; 11.25% H; 4.46% N.

Found: 69.09 11.33 4.45.

EXAMPLE 9 4.3 g DL-lsoleucine, 12 ml 37% formaldehyde solution and 40 ml 60% ethanol were warmed until a homogeneous solution was formed to which a solution of 3.6 g urethane in 20 ml ethanol was added. The resulting reaction was exothermic, and the reaction mixture was stored in a refrigerator to precipitate crystals of N- ethylcarbaminomethyl-DL-isoleucine which were filtered off, washed with acetone and recrystallized from dimethylformamide. The purified, plate-shaped crystals weighed 3.0 g (40% yield) and melted at 166C.

Elementary analysis:

Calculated for C,.,H,,,O N,: 51.70% C; 8.68% H; 12.06% N.

Found: 51.78 8.56 12.12.

EXAMPLE 10 2.4 g L-Threonine, 6 ml 37% formaldehyde solution and 45 ml 60% ethanol were heated until a homogeneous solution was formed to which a solution of 2.86 g B-naphthylamine in 50 ml 60% ethanol was added. The resulting reaction was exothermic, and a small amount of oily material precipitated and was filtered off. The filtrate was stored for several days, whereby crystals of N-,8-naphthylaminomethyl-L-threonine were precipitated. They were recovered by filtration, washed with 50% ethanol, and recrystallized from dimethylformamide. The purified, platelet-shaped crystals weighed 1.9 g (35% yield) and melted at 218C. [a];," 123.52 (C=0.5l, 0.2N NaOH).

Elementary analysis:

Calculated for C H O N 65.68% C; 6.61% H; 10.21% N. Found: 66.65 6.34 9.94.

EXAMPLE 11 A solution of 4.8 g 9-fluorenylacetyl chloride in 20 ml ether was added dropwise over a period of 20 minutes with stirring to a mixture of 3.3 g L-phenylalanine, 8 ml 10% sodium hydroxide solution and 100 ml 10% sodium carbonate solution at room temperature. Stirring was continued for 3 additional hours at room temperature, and the reaction mixture was then made acid to Congo Red with dilute hydrochloric acid. The precipitated crystals of N-9-fluorenylsulfonylacetyl-L- phenylalanine were filtered out and recrystallized from acetone. The purified crystals weighed 5.9 g (80% yield) and melted at 188C.

Elementary analysis:

Calculated for C H O N: 77.60% C; 5.69% H; 3.77% N.

Found: 77.14 5.24 3.61.

EXAMPLE 12 24.6 g Myristoyl chloride and a solution of 10.6 g sodium carbonate in l 10 ml water were added dropwise alternatively over a period of 30 minutes with stirring to a mixture of 13.1 g L-isoleucine, 40 ml 10% sodium hydroxide solution and 60 ml acetone at room temperature. Stirring was continued for additional 30 minutes at that temperature, and the reaction mixture was then made acid to Congo Red with dilute hydrochloric acid. The precipitated crystals of N-myristoyl-L-isoleucine were filtered out and recrystallized from 50% ethanol. The purified, plate-shaped crystals weighed 31 g (91% yield) and melted at 98 99C. [al 530' (C=2.0, absolute ethanol).

Elementary analysis:

Calculated for C H NO 70.04% C; 11.51% H; 4.10% N. Found: 70.26 11.76 3.96.

EXAMPLE 13 A solution of 4.5 g B-naphthalenesulfonyl chloride in 50 ml ether was added dropwise over a period of 15 minutes with stirring to a mixture of 4.1 g DL-tryptophan, 10 ml 10% sodium hydroxide solution and 50 ml 10% sodium carbonate solution at room temperature. Stirring was continued for additional 3 hours, and the reaction mixture was then made acid to Congo Red with dilute hydrochloric acid. The precipitated crystals of N-B-naphthalenesulfonyl-DL-tryptophan were filtered out and recrystallized from ethanol. The purified, plate-shaped crystals weighed 5.0 g (64% yield) and melted at 207C.

Elementary analysis:

Calculated for C H O N,S: 63.94% C; 4.60% H; 7.10% N.

Found: 6383 4.83 7.06.

EXAMPLE 14 16.2 g Propionic anhydride was added to a solution of l 1.7 g L-valirle in 50 ml 33% sodium hydroxide solution. After stirring for 5 minutes, 16.2 g propionic anhydride was again added. Stirring was continued for additional 3 hours, and the reaction mixture was then acidified to pH 3-4 with 6N hydrochloric acid. The

precipitated crystals of N-propionyl-L-valine were filtered out, washed with water and recrystallized from methanol. The purified, columnar crystals weighed 8 g (46% yield, and melted at 137C.

[021 l1.27 (C=1.992, methanol).

Elementary analysis:

Calculated for C H O N: 55.47% C; 8.72% H; 8.08% N.

Found: 55.34 8.55 7.97.

EXAMPLE 15 2.83 g (0.01 Mole) N-furfurylaminomethyl-L- phenylalanine hemihydrate was added to a 5% aqueous solution containing 0.84 g (0.01 mole) sodium bicarbonate to form a clear solution. The solution was concentrated under reduced pressure to crystallize the sodium salt of N-furfurylaminomethyl-L-phenylalanine.

The sodium salts of the other N-substituted amino acids except for N-B-naphthylaminomethylurethane, whose synthesis was described in Examples 1, and 4 to 14, were prepared in the same manner.

EXAMPLE 16 2.07 g (0.01 Mole) N-benzyl-L-valine was added to an aqueous, 10% solution of 0.56 g potassium hydroxide to form a clear solution which was evaporated in a vacuum until the potassium salt of N-benzyl-L-valine crystallized.

The potassium salts of the other N-substituted amino acids described above except for N-B-naphthylaminomethylurethane were prepared in the same manner.

EXAMPLE 17 2.90 g (0.01 Mole) N-furfuryl-L-4-nitrophenylalanine was added to an excess amount of concentrated aqueous ammonia solution to form a clear solution. The solution was concentrated in a vacuum to crystallize the ammonium salt of N-furfuryl-L-4-nitrophenylalanine.

The ammonium salts of the other afore-mentioned N-substituted amino acids except for N-B-naphthylaminomethylurethane were prepared in the same manner.

EXAMPLE 18 EXAMPLE 19 200 kg N-fl-Naphthylaminomethyl-L-leucine, kg corn starch, 80 kg talc, and 2.6 kg magnesium stearate were thoroughly mixed, and 1000 capsules were charged with equal amounts of the mixture in the usual manner. The capsules are employed for the treatment of influenza and of inflammation by oral administration of l to 2 capsules every 6 hours.

7 Capsules containing one or more of the other N-substituted amino acids described above may be prepared in the same manner.

EXAMPLE 20 200 kg N-B-Naphthylaminomethyl-L-leucine, 50 kg lactose, 30 kg corn starch. 3.0 kg magnesium stearate, and [.2 kg light liquid petrolatum were thoroughly mixed and slugged. The slugs were forced through a No. l6 screen. and the resulting granules were then compressed into i000 tablets, each tablet containing 200 mg of the active ingredient.

The above procedure may be similarly applied to prepare tablets containing one or more of the other aforementioned N-substituted amino acids.

EXAMPLE 2] A sterile aqueous solution for intramuscular injection was prepared from 200 g N-B-naphthylaminomethyl-L- lows:

5 Mouse died within 5 days after infection and entire lung was consolidated.

4 Mouse survived at least 5 days, but entire lung was consolidated.

3 75% of lung consolidated.

2 50% of lung consolidated.

1 25% of lung consolidated.

0.5 5 of lung consolidated.

Table 2 lists the mortality and inhibitory effect (the leucine, l0% sodium hydroxide solution, and 1000 ml average value of consolidation scores) for each group water for injection. The active compound was dispersed in the water, and sufficient sodium hydroxide was added to form a solution of pH 7.2. The solution was sterilized by filtration. 1 MI batches of the solution were filled into sterile vials and lyophilized, whereupon the vials were sealed. Immediately prior to use, sufficient sterile water for injection to make 1 ml of solution was added to each vial.

The above procedure may be similarly applied to prepare parenteral solutions of sodium salts of the other N-substituted amino acids except for N-B-naphthylaminomethylurethane.

The physiological effects of the compounds of the invention are illustrated by the following Examples:

EXAMPLE 22 The N-substituted amino acids of the invention prepared as described in Examples 1 and 3 to 14 were each dissolved in dilute aqueous sodium bicarbonate, while only N-B-naphthylaminomethylurethane oxalate prepared as described in Example 2 was dissolved in distilled water. Each of the solutions was sterilized by passage through a microporous filter, and single doses of varying strength were injected intraperitoneally in a standard toxicity test into male mice weighing l0 12 g each. The mean lethal dosage (LD was determined 1 week after the injection. The results obtained are shown in Table l in which the several N-substituted amino acids of the invention are identified by numbers referring to Examples 1 14 in which their preparation is described. For comparison purposes, the known antiviral agent Amantadine (l-Adamantanamine), and the known antiinflammatory agents hydrocortisone and acetylsalicylic acid were also tested.

of ten mice and the dosage employed which was approximately l/5 of LB The eight N-substituted amino acids prepared in Examples l to 8 were suspended in an aqueous 1% carboxymethylcellulose solution, and single doses of varying strength were injected intraperitoneally into one group of male rats weighing 180 g each. 30 Minutes after the injection, the soles of 1 foot in each rat were inoculated with respective 0.] ml doses of the irritating agents listed in Table 3. The edema caused in the inoculated foot was measured by volume comparison with a control foot of the same rat I hour and three hours after the inoculation. The mean effective dosage (ED of each tested compound in mg/kg which reduced the edema volume by 50% is listed in Table 3 together with corresponding values for hydrocortisone and acetylsalicylic acid. The first line for each irritating agent shows the 1 hour values, the second line the three-hour values. IE in the Table indicates that the Table 1 Compound I 2 3 4 5 6 7 8 9 LB mg/kg 1500 I500 650 I500 I500 I500 I500 I80 I500 Compound [0 I l [2 l3 l4 Amantadine Hydrocortisone LD, mg/kg 1500 1500 850 750 233 1250 Acetylsalicylic acid EXAMPLE 23 Groups of [0 mice each were injected intraperitoneally with single doses of solutions of eight compounds tested compound was ineffective.

Table 3 Hydro- Acetyl- Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex.

corsalicylic tisone acid 1 2 3 4 5 6 7 8 Bradikinin (50 glrnl 25 50 2.7 10 75 I0 IE 10 25 22.4 saline soln) 25 50 10 IE 150 10 IE IE 25 10 Serotonine (0.04% in 50 125.4 200 IE IE IE IE IE 1E 30 distilled water 50 150 75.2 250 75 l00 IE 250 IE 30 Formaldehyde (3% in 50 50 50 100 10 150 100 100 25 83.3 distilled water 78 200 10 IE l83 10 200 IE 5 22.6 Kaolin in 40 100 IE l00 10 392 50 100 5 10 distilled water 46 70.5 286 IE IE 392 120.5 IE 5 10 Hyaluronidase (200 50 IE 100 10 182 IE 100 IE 10 'y/ml saline soln) 25 50 80 10 10 80 IE 10 50 10 Dextrane sulfate (0.5 26 200 75.2 10 I99 80 50 10 50 10 in dist'd water) 10 65.3 77 IE 84.3 80 100 IE IE 55.6 Egg White (15% in 78 200 2.7 100 IE 50 IE 100 IE 10 saline soln) 10 70.5 10 50 IE 50 IE 50 IE 10 Carragenin (1% in 40 172 I50 100 85.4 200 IE l00 5O 10 saline soln 25 I00 l00 250 84} 150 IE 250 50 10 Yeast extract (10% 25 200 IE [E 177 IE IE IE I00 in distd water) 50 200 IE 400 IE IE 10 400 I00 10 Mustard (2.5% in 10 50 150 IE I50 150 70.1 IE 5 10 distilled water 15 50 2B5 200 I 50 28S 85.1 200 5 50 EXAMPLE 25 EXAMPLE 26 Mice weighing 20 30 g each were arranged in matched groups of three and were injected each intraperitoneally with one million Ehrlich ascites tumor cells per 10 g of body weight. Immediately after the injection and once daily for the next five days, the mice of the several groups, except for one control group, were given intraperitoneal injections of solutions prepared in the manner of Example 15 from the compounds synthesized in Examples 9 14 respectively, and solutions of Mytomycin-C and Bleomycin, known anti-tumor agents. The daily dosage was one tenth of LB, for each tested compound.

The mice were weighed daily for ten days, the average weight increases for each group were calculated from the nine weight changes as compared to the first days weight, and the inhibiting effect of the tested compound was calculated from the average weight increase so determined and the corresponding weight increase for the untreated control group. Table 4 lists the reduction in body weight increase in the treated mice as percentage of the body weight increase of the control group.

After the ten days, the mice were sacrificed, and the tumor cells in the ascites were counted. The inhibition of tumor cell growth is listed for each tested compound in Table 4 as the difference between tumor cells in treated and control animals as percentage of the number of tumor cells in the latter.

Table 4 Inhibition of tumor cell growth (5) Inhibition of body weight increase:

Groups of mice as in Example 25 were also infected with implanted cells of Sarcoma 180 solid tumor. 24 Hours after tumor implantation, the mice of respective groups received the dosages of Mitomycin-C and of solutions of Compounds 9, ll, l3, 14, that is, the compounds synthesized in Examples 9, ll, l3, l4 and dissolved as in Example 15, by intraperitoneal injection. The injections were repeated twice in one-day intervals. A control group remained untreated.

The mice were each weighed at the beginning of the test and after 21 days. They were then sacrificed, and the tumors were weighed. Table 5 lists the average weight increase for each group and the standard deviation for each set of three weight differences, also the inhibition of tumor growth in percent of the average tumor weight in the control group.

Table 5 Daily dosage Average weight Inhibition of Sample mykg increase, g tumor growth,

Control 5.3211 Mitomycin-C 1.5 2.5:13 71.7 Compound 9 300 3711.5 82.3 Compound 11 35 4.11-21 60.5 Compohnd I3 32:1.8 84.1 Compound 14 300 4.5a) 74.9

EXAMPLE 27 Table 6 daily average increased Sample LD dosage survival survivors life span (mg/kg. oral) (mg/kg) (days) Control 9.8:10 /8 Milomyc'm-C 65 I3 I0.B:3.5 4H0 10.2 Bleomycin 300 3O l6.5t7.3 3/10 68.4 Compound 9 500() lOOO 15.4:34 3/10 57.] Compound ll I850 370 11.1129 2/7 13.3 Compound 14 5000 I000 l4.6t5.6 /7 49.0

Survivors a! he time of he death ol the controls.

What is claimed is:

l. N-Ethylcarbaminomethylisoleucine.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,919 ,291

DATED November 11, 1975 INVENTOMS) I SHIGESHI TOYOSHIMA ET AL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the heading, line [30], after "Foreign Application Priority Data" insert Sept. 6, 1969 Japan 70716/1969 Signed and Scaled this seventeenth Day Of February 1976 [SEAL] Arrest.

C. MARSHALL DANN RUTH C. MASON I Commissioner nj'Parents and Trademarks Arresting Officer 

1. N-ETHYLCARBAMINOMETHYLISOLEUCINE. 